Roller weir



Sept. 25, 1934. K. scHON- 4 OLLER WEIR Filed 001:. 3, 1933 PatentedSept. 25, 1934 UNITED ,STATES PATENT OFFICE.

ROLLER WEIR Application October 3,

1933, Serial No. 692,046

In Germany October 14, 19722.

3 Claims.

This invention relates to roller weirs and more particularly tothe-runways upon which the roller weirs are designed to move. Incomparison with floodgates which travel in a perpendicular direction,roller weirs have the disadvantage of requiring considerably greaterpier lengths, which are necessitated by the inclined tracks upon whichthe rollers run. In order to overcome this disadvantage, attempts havebeen made previously to provide perpendicular runways. for

roller weirs also. In this construction, the resting point of the rollerweir on the runways is considerably higher than that in the constructionhaving inclined runways. As a result of this higher resting point in thevertical arrangement of the runways, a larger tractive force isnecessary to raise the roller from its damming position, whereuponoperating and winding mechanisms of substantially higher capacities arerequired.

It is the object of the invention to provide a roller weir in which thetwo disadvantages mentioned above are eliminated, in which the piers maybe maintained proportionately short inthe direction of the stream, andthe force required to lift the roller weir from its damming position isno greater than that required in the case of an arrangement havinginclined runways. These objects are attained by designing the runways sothat the lower parts thereof extending within the field of the watercurrent are inclined, and above the dammed water level, the runways passsuddenly or gradually into a steeper portion which may runperpendicularly or approximately One embodiment of the invention isillustrated in the accompanying drawing which shows a sectional view ofthe roller weir with certain parts in elevation, in Fig. 1, and

Fig. 2 is a plan view of Fig. 1.

The roller weir 1 is shown in its damming position, having a beak-shapeddamming plate 2 terminating in a jointed strip 3 resting on the bottom4. The ends of the roller extend in recesses in the sides of the piersand are fitted at each end with a gear wheel 5 which engages with atoothed bar or track 6. These toothed bars, which constitute the runwaysof the roller, extend upwardly in an inclined direction at the lowerends thereof in the field of the water current and in the same directionas the water current. Above the dammed water level, the lower portion ofeach of the bars 6 passes through a circular arc, whose radiusissuitably slightly greater than the radius of the gear wheel 5, and 55then into a steeper portion, the final direction of which may beperpendicular or nearly so. For the purpose of lifting the roller, araising means 7 is provided.

In the course of raising the roller from its damming position. it isnecessary to overcome not only the weight of the roller, but also theforce of the water presure imposed thereon. The application point of theaverage force of the water pressure is known to be at approximately athird of the damming height and is illustrated by the arrow .1: in thedrawing. The greater the difference in level between this applicationline and the points at which the roller rests on its rimways, thegreater is the force necessary to raise the roller. The numeral 8 in thedrawing designates the resting points of the roller upon the runways inan arrangement in which the latter extend perpendicularly, as indicatedin the dot and dash line in the drawing. By such an arrangement, adifierence in level amounting to a exists between the resting points ofthe roller and the point of application of the average force of thewater. Accordingly, in order to raise the roller in such a verticalarrangement of the runways, a tractive force is necessary which isdetermined by the distance a, and which is proportionately large. On theother hand, according to the instant invention, in the inclinedatrangement of the lower portions of the runways, the resting points ofthe roller are'at 9, which results in a substantially smaller differencein level between these resting points and the abovementioned point ofapplication of the average force of the water. This difierence in level"b, being substantially smaller than a", requires a considerably smallertractive force in order to raise the roller from its damming position.Since the force of the water pressure upon the roller weir decreases asthe latter is raised, and at the position of the roller above the watersurface, this force becomes equivalent to zero, it is possible for therunways to extend upwardly at about this point in a steeper direction,and finally they may run vertically in order to attain as short a pieras possible; The lengthening of the piers in the arrangement of therunways according to the instant invention in comparison with thelengths of the piers in which the runways extend vertically, results ina difi'erence which is represented by the quantity 0 in the drawing,which for all practical purposes is insignificant.

Having described my invention, I claim:

1. In an apparatus of the class described, a roller weir adapted to dama body of water, a runway for guiding said roller weir in the course ofof its being raised from its damming position,

said runway extending upwardly in a direction inclined from the verticalat the lower portion thereof within the field of the water current andin the same direction as the water current, to lower the resting pointof the roller weir upon said runway, said runway furthermore passingthrough an are having a radius greater than that of said roller weir atabout the surface level of the dammed body of water, and passing into aportion extending in at least a nearly perpendicular direction beyondthat are.

3. In an apparatus of the class described, a roller weir adapted to dama body of water, a pier at each end of said weir, a recess in each ofsaid piers for guiding said roller weir, a gear wheel mounted on eachend of said roller weir within each of said recesses, a toothed bar ineach recess for carrying each of said gear wheels, each toothed barextending upwardly sloping in a direction inclined from the vertical atthe lower portion thereof within the field of the water

